The primary purpose of this study is to evaluate Neoral the new FDA approved formulation of the drug cyclosporine A as compared to the old form, Sandummune Soft Gelatin Capsules. Neoral was developed as a drug to prevent rejection following organ transplantation. Neoral is better absorbed after oral dosing and its absorption is less effected by food. Previous studies documenting this were done in new transplants or by comparing between patients on Sandimmune versus Neoral. The current study is designed to confirm these findings by comparing the variability of cyclosporine absorption within patients. This will be tested by comparing the pharmacokinetics and safety of Neoral with Sandimmune Soft Gelatin Capsules, when used in combination with other routine treatments for the prevention of rejection in stable renal transplant patients. The study will be a multicenter, open labeled trial involving about 50 patients. Only stable recipients of a renal transplant who are at least six months after their transplant will be studied. The primary objective is to demonstrate that stable renal transplant patients converted from Sandimmune to Neoral have a reduction in the variability of cyclosporine absorption. Patients who meet the study criteria and sign the consent, will be admitted five times to the GCRC for formal pharmacokinetics studies. The first 3 thimes will be on their current formulation of Sandimmune. After the third PK study, the patients will be converted to Neoral, and two additional PKs will be done.